LEM procon Owner's Manual

The lighting flash with arrowshad symbol within an
equilateral triangle is intended to alert the user to the
presence of uninsulated “dangerous voltages” within the
product’s enclosure, that may be of sufficient magnitude to
constitute a risk of electric schok to persons.

The excalamation point within an equilater triangle is
intended to alert the user to the presence of important
operating and maintenance (servicing) instructions in the
literature accompanyng the appliance.

IMPORTANT SAFETY INSTRUCTIONS

INSTRUCTIONS PERTAINING A A RISK OF FIRE, ELECTRIC SHOCK OR INJURY A PERSONS

WARNING - When using electric products, basic precautions should always be folowed, including the following.

1. Read all the SAFETY INSTRUCTIONS before using the product.

2. A reduce the risk of injury, close supervision is necessary when the product is used near children.

3. Do not use this product near water - for example, near a bathtub, washbowl. kitchen sink, in a wet basement

or near a swimming pool or the like.

4. This product in combination with speaker boxes, may be capable of producing sound levels that could
cause permanent hearing loss. Do not operate for a long period of time at high volume level or at level that
is uncomfortable. If you experience any hearing loss or ringing in the ears, you should consult an audiologist.

5. This product should be located so that its location or position does not interfere with its proper ventilation.

6. This product should be located away from heat sources such as radiators, hest register or other product

that produce heat.

7. The product may be connected a a power supply only of the type described on the operating instructions
or as marked on the product.

8. The product may be equipped with a polarized line plug (one blade wider then the other). This is a safety
feature. If you are unable a insert the plug into the outlet, contact an electrician a replace your obsolete
outlet. Do not defeat the safety purpose of the plug.

9. The power-supply cord of the product should be unplugged from the outlet when left unused for a long
period of time. When unplugging the power-supply cord, do not pull on the cord, but grasp it by the plug.

10. Care should be taken so that object do not fall and liquid are not spilled into the enclosure through
openings.

11. The product should be servived by qualified service personnel when:
A. The power-supply cord or the plug has been damaged; or
B. Objects have fallen, or liquid has been spilled into the product; or
C. The product has been exposed to rain; or
D. The product does not appear to operate normally or exhibits a marked change in performace; or
E. The product has been dropped or the enclosure damaged.

12. Do not attempt to service the product beyond that described in the user-maintenance instructions.

All other servicing should be referred to qualified service personnel.

13. WARNING - Do not place objects on the product’s power cord or place it in a position where anyone
could trip over, walk on or roll anything over it. Do not allow the product to rest on or to be installed over
power cords of any type. Improper installations os this type create the possibility of fire hazard and/or perso­nal injury.

SAVE THESE INSTRUCTIONS

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Contents

Contents

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Instructions and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Functions & Controls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Connection panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Connection examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Connection cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Technical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

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Congratulations for having chosen PROCON amplifiers!

The PROCON SERIES power amplifiers have been designed by LEM in order to provide great
efficiency, dynamics and reliability at a very affordable price, in a variety of fixed and mobile audio
applications.

The accurately designed circuitry and selected components offer excellent sound quality and high
fidelity audio reproduction. The compact design improves the price/performance ratio, while the rugged
metal chassis guarantees maximum sturdiness.

The PROCON SERIES amplifiers are available in six models with various power ratings.

200+200W

375+375W

475+475W

550+550W

625+625W

750+750W

The PROCON SERIES amplifiers are equipped with a highly visible LED display system, which
provides precise information on signal status in any lighting conditions. The connection system includes
XLR and TRS JACKS for audio input and SPEAKON and BINDING POST for power outputs. Standard
19” rack mount together with sturdy metal chassis make installation easy while providing maximum
protection.

Introduction

Introduction

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Instructions and installation

ATTENTION !!!

The PROCON series amplifiers generate high voltage on output.
To avoid the risk of electric shocks, DO NOT TOUCH any bare wires when the unit is
switched on.
This manual contains important information for correct safe use: read it carefully
before using your amplifier.

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Connection to the mains supply

Before connecting the amplifier to the mains socket, always make certain that:

- the electric system and mains socket have an adequate grounding, compatible with the safety norms
(if you’re uncertain, consult specialized personnel);

- the mains voltage corresponds to that shown on the rear of the unit (an allowance of up to ±10% is
accepted);

- the power cord is not damaged and has no bare wires;

- the on/off switch is in the OFF position.
Make sure the amplifier is also off before disconnecting the power cord from the mains socket.

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Switching on and off

In your sound reinforcement system,

always switch on the amplifier after all the other equipment and
always switch it off before anything else, if possible with the Gain controls set at minimum: this will avoid
annoying and sometimes dangerous signal peaks.

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Installation and use

Your PROCON amplifier generates decidedly high power, so install it in locations which ensure correct
air circulation. Avoid long exposure to direct sunlight, sources of strong heat, powerful vibrations, very
dusty or particularly damp surroundings or (even worse) rain: this will avoid possible faulty operation,
deterioration or even electric shocks and fires.
The air for cooling the unit is forced in through the vents in the front panel and out through those on the
rear panel, so make certain that there’s sufficient space round the amplifier to allow adequate air
circulation.
If racks or flight-cases are used, make sure that airflow is unobstructed:

don’t install the amplifiers in
racks or flight-cases with closed backs.
Since part of the heat is dissipated via the metal bottom of the amplifier,

it’s advisable to install the

amplifiers with at least one rack unit space between them.

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Audio connections

Remember to always connect and disconnect other units with the amplifier switched off.
Always use good quality cables of the appropriate type, opportunely described in the “Connection Cables”
chapter of this manual.
Take care of your connector cables, a very frequent cause of small/big problems. Check their condition fre-

quently . Always grip them by the connector, avoid pulling them forcefully and wind them without forming knots
or sharp bends: they’ll last longer this way and be more reliable, which is a definite advantage.

Instructions and installation

4

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Preventing or identifying interference

First of all, check that the amplifier is installed in a place free from industrial or RF (radio frequency) interfer­ence. Avoid installing your equipment very near radio or TV sets, mobile phones, etc., as these can cause
noisy interference.
When connecting the other components of your sound system, watch out for the so-called “ground loops”,
which could cause hum and jeopardize the amplifier’s excellent Signal-to-Noise and low distortion character­istics.
The best way (even if not always feasible) to avoid ground loops is to connect the electric ground of all the
equipment to a single central point (the so-called “star” system). In this case, the central point in sound
systems is the mixer.
To help identify the cause of any interference, connect the various sections of the mixer to the rest of the
equipment in the following order, listening to the resultant sound as you proceed with connection:

Outputs: amplifiers + loudspeaker enclosures (Master outputs);

amplifiers + monitors (AUX outputs);
effects (AUX outputs or EFF send/return).

Inputs: instruments with line signals (keyboards, samplers, recorders, etc.);

microphones (lastly and one by one).

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Protection and maintenance

The amplifier is built in shock-resistant material. Nevertheless, protect it during transport with a flight-case to
avoid the risk of any casual accidents.
After long periods of use, particularly in dusty surroundings, accumulated dust may interfere with the

unit’s cooling.

Without opening the amplifier and making certain it’s disconnected from the mains supply,
dust can be removed with a jet of compressed air, forcing it out through the chassis’ louvers. If the dust
build-up is excessive, don’t open the amplifier, as you could run the risk of serious electric shocks: contact
the nearest

Assistance Centre

Any dust on the outside of the chassis should be removed using a dry soft cloth or brush. Never use
alcohol, acetone or solvents of any kind.
The amplifier requires no further maintenance.

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In the event of breakdown

All user-adjustable parts are external and easily accessible.
Never open the amplifier: you could run the risk of serious electric shocks.
In the event of breakdown, contact the nearest

Assistance Centre

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Keeping the documentation

Keep this user’s manual for future consultation.
Also remember that the mixer will get a better price on the secondhand market if (as well as being in good
condition) if it has its original documentation and packaging.

Instructions and installation

5

Functions & Controls

Functions & Controls

POWER ON/OFF

ON - OFF switch.

POWER ON LED

LED indicating when the amplifier is switched on.

INPUT ATTENUATORS

Input gain attenuator potentiometers.

Attenuate the level of the external signal sent to the respective channels of the amplifier.
Continuously variable values, expressed in dB, are between:

“

∞∞

∞∞

∞”: fully closed (the signal is completely attenuated and therefore not sent to the channel

of the amplifier) and

“0”: fully open, i.e. nominal level (the signal is not attenuated in any way, so is fed to the amplifier

channel at the same level at which it arrives on input)

SIGNAL LEDs

Indicators of signals on input.

If lit, indicate that the relative inputs of the amplifier channels are receiving an audio signal.

CLIP LEDs

Amplifier CLIPPING indicators.

Indicate the clipping of the amplifier, i.e. when the audio signal level exceeds the output capacity of the
amplifier channel. When these LEDs flash reduce the input signal level.

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INPUTS

Balanced XLR-F connectors (0 dB).

The inputs of the amplifier’s two channels. Can receive balanced or unbalanced high impedance line
signals from equipment with high level outputs.

NB: Whenever possible, use balanced cables. In any case, avoid using a balanced cable for one channel and an unbalanced
one for the other, as this would cause a considerable difference in channel levels.

LINK

Balanced JACK connectors (0 dB).

These connectors are connected in parallel with the respective XLR-F connectors. This enables a second
unit (e.g. another amplifier) to be daisy-chained to the first. It’s thus possible to power several amplifiers
using the same signal, forming more powerful sound reinforcement systems.

OUTPUTS

SPEAKON + BINDING POST connectors (minimum impedance 4

ΩΩ

ΩΩ

Ω). The SPEAKON connectors are

wired in this way:

- PIN 1+ connected in parallel to the “+” BINDING POST “+” (red color);

- PIN 1- connected in parallel to the “-” BINDING POST “+” (black color);

- PIN 2+ and 2- NOT connected.

NOTE: to avoid possible damage to the loudspeaker enclosures, only connect enclosures or speaker systems compatible
with the power load and impedance limits indicated for the amplifier (regarding this, consult the “Technical specifications”
chapter for reference to your specific amplifier model). Use only loudspeaker enclosure cables, never signal cables, i.e. those
normally used for microphones, instruments and audio equipment in general.

A.C. ~

Power cord.

Connection panel

Connection panel

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Connection examples

Connection examples

8

Connection examples

9

Connection cables

The following diagrams show the wiring of the connectors that can be used with the PROCON series amplifiers.
To connect the mixer outputs to the amplifiers inputs, make certain to always use balanced signal cables: the use of unbalanced
cables could in fact probably cause annoying hum and noise.
To connect the amplifier to the loudspeaker enclosures always use power cables (speaker cables made up of two wires, normally
with a large cross-section).
Take care of your connector cables, always gripping them by the plugs, avoid pulling them directly and winding them without
knots or bends: they’ll last longer and be more reliable, which is to your advantage. Check periodically that your cables are in
good condition, correctly wired and with perfectly efficient contacts: in fact many problems and drawbacks (false contacts,
ground hum, crackles, etc.) are caused by the use of unsuitable or damaged cables.

Connection cables

SPEAKON power connector

Balanced JACK signal connector

Balanced XLR-M signal connector

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Technical specifications

Technical specifications

POWER SPECIFICATIONS

400 750 950 1100 1250 1500

EIA output power

1kHz, THD maximum 1%
Both cha nnel s

8 Ohms
4 Ohms

125+125
200+200

215+215
375+375

275+275
475+475

300+300
550+550

375+375
625+625

450+450
750+750

ELECTRICAL SPECIFICATIONS

400 750 950 1100 1250 1500

INPUT SENSITIVITY

INPUT IMPEDANCE

FREQUENCY RESPONSE

VOLTAGE GAIN

32dB 33dB 34dB 35dB 36dB 37dB

SLEW RATE

DAM PING FACTOR

CROSS TA LK

S/N ratio

Harmonic distortion THD

Intermodulation distortion SMPTE

GENERAL SPECIFICATIONS

400 750 950 1100 1250 1500

PROT ECTIONS

CONTROLS

INDICATORS

CONNECTORS

IN

OUT

POW ER SUPPLY

DIMENSIONS

mm (WxHxD)

WEIGHT

k

g

11 12.8 14.6 16 18 21

1 XLR-F + 1 JACK in parallel for each c hannel

1 BINDING POST + 1 4-way SPEAKON for each channel

<0.1% (SMPTE method, 60Hz & 7kHz, 4:1 ratio)

Power transformer thermal protection

Short circuit protection

Sensor for current on out puts

ON/OFF switch

21-detect input level control for each channel

POW ER ON: 1 red LED

SIGNAL: 2

g

reen LEDs

CLIP: 2 red LEDs

483x88x370 483x88x425

see lab el on the unit

-82 dB (1KHz)

-98 dB

<0.1% (ref 20Hz -20KHz)

0dB (0.775V)

10 k Ohms (balanc ed)

10÷50000 Hz (-0.5dB)

>400:1 @ 1kHz, 8Ohms

22 V/ms

FEDERAL COMMUNICATIONS COMMISSION

NOTE: This equipment has been tested and found to comply with the limits for a Class A

digital device, pursuant to Part 15 of FCC Rules. These limits are designed to provide
reasonable protection against harmful interference when the equipment is operated in a
commercial environment. This equipment generates, uses and can radiate radio frequency
energy and, if not installed and used in accordance with the instruction manual, may cause
harmful interference in which case the user will be required to correct the interference at his
own expense.

CAUTION: Changes or modifications to this product not expressly approved by the
manufacturer could void the user’s authority to operate this product.

Le informazioni contenute in questo documento sono state attentamente redatte e controllate. Tuttavia
non è assunta alcuna responsabilità per eventuali inesatezze.
Tutti i diritti sono riservati e in questo documento non può essere copiato, fotocopiato, riprodotto per intero
o in parte senza previo consenso scritto della GENERALMUSIC S.p.A.
GENERALMUSIC si riserva il diritto di apportare senza preavviso cambiamenti e modifiche estetiche,
funzionali o di design a ciascun proprio prodotto.
GENERALMUSIC non assume alcuna responsabilità sull’uso o sull’applicazione dei prodotti o dei circuiti
qui descritti.

STAMPATO IN ITALIA

The information contained in this publication has been carefully prepared and checked. However no
responsibility will be taken for any errors.
All rights are reserved and this document cannot be copied, photocopied or reproducted in part or
completely without written consent being obtained in advance from GENERALMUSIC S.p.A.
GENERALMUSIC reserves the right to make any aesthetic, functional or design modification to any of its
products without prior notice.
GENERALMUSIC assumes no responsibility for the use or aoolication of the products or circuits
described herein.

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Sales Division: 47842 S.Giovanni in Marignano (RN) – Via delle Rose, 12 – tel. [phone] – fax [phone]

Internet: http://www.lemaudio.com